Key to the third instars of New World Phileurini

Modified from Neita & Ratcliffe (2011), Ratcliffe & Skelley (2011), Ibarra-Polesel et al. 2017.

1. Anterior frontal setae absent............................................................................. 2

- Anterior frontal setae present............................................................................ 7

2. Lateral margins of labrum broadly rounded, not angulate (Argentina, southern Brazil, Paraguay, Uruguay)................................................................................... Trioplus cylindricus (Mannerheim, 1829)

- At least one lateral margin of labrum angulate............................................................... 3

3. Left and right lateral margins of labrum angulate. Maxilla with a row of six conical, stridulatory teeth (Uruguay, Brazil).................................................................... Archophileurus fimbriatus (Burmeister, 1847)

- Left lateral margin of labrum angulate. Maxilla with 6–10 stridulatory teeth....................................... 4

4. Terminal antennomere with 5 dorsal sensory spots........................................................... 5

- Terminal antennomere with less than 5 dorsal sensory spots....................................................6

5. Abdominal spiracle I smaller than spiracles II–VII. Maxilla with row of 6–7 truncate, stridulatory teeth (Colombia)......................................................................... Hemiphileurus elbitae Neita & Ratcliffe, 2010

- Abdominal spiracles similar in size. Maxilla with row of 7–10 truncate, stridulatory teeth (United States of America to Pan- ama).......................................................... Phileurus truncatus (Palisot de Beauvois, 1806)

6. Terminal segment of antenna with 2 dorsal sensory spots. Inner margin of left mandible, distad of molar area, with short, rounded tooth (Hispaniola)................................................... Hemiphileurus dispar Kolbe, 1910

- Terminal segment of antenna with 3–4 dorsal sensory spots. Inner margin of left mandible, distad of molar area, with promi- nent, triangular tooth (United States of America, Mexico)....................... Hemiphileurus illatus (LeConte, 1854)

7. Protarsal claw longer than mesotarsal and metatarsal claws.....................................................8

- Protarsal claw similar in size to mesotarsal and metatarsal claws.............................................. 11

8. Surface of head coarsely pitted, with dense covering of setae. Stridulatory area of mandible formed by approximately 30 sepa- rated ridges (Brazil)...................................................... Actinobolus trilobus Lüderwaldt, 1910

- Surface of head moderately punctate and sparsely setae. Stridulatory area of mandible formed by 40 or more separated ridges....................................................................................................9

9. Left lateral margin of labrum angulate................................................................... 10

- Lateral margins of labrum broadly rounded, not angulate (northeastern South America)................................................................................................ Homophileurus luederwaldti (Ohaus, 1910)

10. Anterior clypeal setae absent (Brazil, Paraguay)........................... Homophileurus integer (Burmeister, 1847)

- Anterior clypeal setae present (Mexico to Brazil)............................... Homophileurus tricuspis Prell, 1914

11. Ocelli absent....................................................................................... 12

- Ocelli present....................................................................................... 13

12. Right lateral margin of labrum rounded, raster and lower anal lobe with short setae alternates with numerous long setae (South America)............................................................ Archophileurus vervex Burmeister, 1847

- Right lateral margin of labrum angulate, raster and lower anal lobe with short and thin setae ( United States of America to Argentina)................................................................. Phileurus valgus (Olivier, 1789)

13. Lateral margins of labrum broadly rounded, not angulate. Laephoba with 11 slender, short setae Maxilla with a row of 7 strid- ulatory teeth (Mexico to Paraguay)........................................... Phileurus didymus (Linnaeus, 1758)

- Left and right lateral margins of labrum angulate. Laephoba with 17 slender, short setae. Maxilla with a row of 9 stridulatory teeth (French Guiana, Brazil, Uruguay)......................................... Phileurus affinis Burmeister, 1847